Mutual precipitation of polyamides and cellulose



K. THINIUS April 25, 1944..

MUTUAL PRECIPITATION OF POLYAMIDES AND CELLULOSE Filed Aug. 24. 1940 l O on 0 lo 0; I 00000 00000 O OOOMOOM -w m 7 OOOO OOOO WO OO OOOO0 0 0- .Zhvenfor (0P7 raw/us 19 7%? C:

Patented Apr. 25, 1944 UNITED STATES PATENT OFFICE i/ZL I f: I MUTUAL. RECIPITATION OF PULYAMIDES AND cELLuLosE Kurt Thinius, silx'i bnr Germany; 'vested in the AIien' Property Custodian Application August 24, 1940, Serial No. 354,117 In Germany August 6, 1939 Claims. I (01. 18-54) This invention relates to the production of tives, compared with the pure polyamide strucmixed structures, foils, filaments, films consisting tures, have the advantage of showing their maxiof polyamides and cellulose or cellulose derivavmal'mechanical properties immediately after the tives. removalflof the liquid, so that the subsequent The 50 called Polyamides being h p lymeric 5 heat-treatment,-.as mentioned above, is not necescompounds are obtainedby polycondensatlon-of sary any more.- ":This. represents a considerable bifunctional compounds, for instance by polytechnical progress.- "Furthermore it must be condensation of w-amino carboxylic acids with mentioned that-the high absorptiongof water of, more than five carbon atoms between the aminofor instance; 8-20% according-to time and temand carboxyl groups or their amide formingjdeperature, whichis characteristic for the polyrivatives, furthermore by polycondensation 1 of amides, has decreased considerably. in;the mixed w-diamines with {our and more atoms-between structuresobtained according to.- the presentinthe .two amino groups and dicarboxylic acidsor vention. -Wh'reas the high sensitivityagainst their iunctionalderivatives, such ase'sters, acid water limits," considerablyithe-held of applicachlorides, lactams, urethanes, au-dihalogen byetion for thelpolyamideacthesmixed-structures dl'OCBI'bOIlS. Theirrproperties in regard to soluconsistingaot polyamidesmndicellulose or-cellue bility makciitzdifficult to work them up inthe lose derivativesareusefulcwherever-othenwaterusual wayby dissolving them-inorganic solvents repellent substanceshave-been.applied; r :at ordinary or slightly increased temperature; It .-.1 Reference is made-to, the accompanying draw is possibletoiormthe polyamides thermally,- on 0 .ingl forming i'at-part loft.thislzapplication which account of. the high temperatures; however 'this drawing :illustrates preferredimeans of shapin involves many technical: 'difilcultieswii Moreover, .thei mixed-structuresof this; invention asand in it was found-necessary togive a-iurt-hentreatpwhichu. 1':-

rm mentto the structurespfllms; foils orxfilaments "'11. FlgLue-Fl isfa cross section-ct a;d0uble-:tube thus obtained-in order-to attainumaximai -mee consisting ,ofi'twoiconcentrlc;:tubes whichijconchanical properties. This can either consist in verge-rat one-endrto a common-opening;

a cold drawing process (in two directions at right v. eFigure .2 ;is. a: cross Seem-On:OfiB-ILzCHdIQSS -.belt angles to each other) which is always connected ;and-.two; hoppers-superimposedlthereonms =z,.;; with a change in the thickness of the structures, Figure 3 is a perspective viewaofa ajfilm; one or in a iurther heat treatment at temperatures 3 end of which is shown in the cross section.

above 180' C. All these additional measurements As seen fromthe side of the cellulose or its render the working-up process more difllcultl derivatives the mixed structures with polyamide It is an object oi the present invention to prohave the advantage of increased flexibility, duce mixed structures, toils, films; filaments and higher stability on heating and better dyeing the like. characteristics. The following examples may A iurther object is to manufacture said strucfurther exemplify the present invention. tures from polvamides and cellulose. r Eam le 1 Still another object is to produce-these strucp tures from polyamides and cellulose derivatives. s; For the manufacture 01 a. mixed structure in These and otherobjectswill become apparent 4 -;;the form of as him consisting oi polyamide and from the iollowing description. cellulose glycolic acid there are di ssolved 20 parts These aiorementioncd disadvantages can be a or polyamlde of a medium degree" of condensaellminated when the polyamides are worked up tion correspondlngto a K- value or about 35 (in together with cellulose or its derivatives which regard to K-valuo see Cellulosechemie 13, 73 by are soluble in alkaline media. This isaccom- Fikentschery'ino 11 aqueous hydrochloric acid.

plished by the iollowing process. The polyamides This is precipitated througha large slot in a are'dissolved in acid mediums 01 at least sixprecipitating bath consisting of a solution or 10 times normality, whereupon these solutions are r parts cellulose sodiun'rglycolate m so parts 6 n precipitated by an alkalinesolution or a discaustic soda. The precipitating bathflows tothe solved cellulose or cellulose derivative, it ncces- 5 polyamido solution preierably in a counter-cursary alter nitration. The polyamide and the "rent. The aim obtained on the place or the cellulose particles are thereby homogenously entry consists or polyamide and cellulose glycolic mixed with each other and give a mixed strucacid. The proportion oi the two constituents is ture 0! excellent properties. The mixed strucdetermined by the proportion of the alkaline tures consisting of cellulose or cellulose derivacellulose giyculic acid solution to the polyamide solution. It a mixed film being rich in poiy- WhatIclaimis: amide is desired, the alkaline precipitating bath 1. A process for the production oi mixed strucwill be used in a normality smaller than 6 n. It tures, ioiis, films and filaments from polyamides is also possible to dilute carefully the acid polyand celluloslc material, which process comprises amide soution up to about of its volume with c mixing a solution of a po y in mineral acid water and to work it up into mixed films by with an alkaline solution of the cellulosic material means of cellulose glycoiio acid as described while shaping the two solutions to the desired above. Also the reverse working process, nameform, whereby the polyamide and the celluiosic 1y to precipitate the cellulose derivative in a material are precipitated from their respective precipitating bath consisting of a polyamide solutions in the form desired. solution is possible. 2. A process for the production or mixed struc- Emmpm H hltures, Ioils, films and filaments from polyamides 1 J1 and cellulose, which process comprises mixing a A polyamide solution according to Example I solution oi a polyamide in mineral acid with an flows through the inner part or a double-tube ldlalk'aline celluiosio solution while shaping the two and meets at the opening a cellulose solution in solutions to the desired form, whereby the polyammoniacal copper oxide.- A mixed-filament amide and-the cellulose are precipitated from consisting of polyamide and cellulose is obtained'. their respective solutions in the form desired. The mixed filament, the shape or which depends 3. A process for the production of mixed strucon the iorm oi the double-tube or of the nozzles 20 three, foils, films and filaments from poiyamides is characterized by an increased stability against andceilulose, which process comprises mixing a water as compared with the pure polyamide filasolution oi'- a 'polyamide in mineral acid with an ment.- This is true even when the cellulose portion ammoniacalsolution of cellulose while shaping remains below that of the polyamide. The man'- the two solutions to the desired form, whereby uiacture of a mixed structure, for instance in the 2c the polyamide and the cellulose are precipitated form 0! i'oils, may be accomplished also in the from their respective solutions in the form deioilowing manner: The openings 01' the polyamide sired. solution and oi the alkaline solutions of cellulose 4. A process for the production 01- mixed strucor cellulose'derlvatives being right close to each tures.:ioils,-fi1ms andnlaments from polyamides other are conducted in water or in 2-4 times n -80 and-cellulose compounds which process comhydrochloric acid in'such a manner, that mixing prises mixing a solution oi a-poiyamide in minor the solutions-and consequently formation 0! a eral' acid with an -alkaline solution oithe celmixedfilmoccurs. .1 1 lulosdcompound-while shapingthe'two solutions Instead ot-the' ammoniacarcopper oxide-celluin-thcdesired form, whereby the-'polyamide-and lose solution-a solution oi tho cellulose others or as the cellulose compound 'are precipitated from ot-the ether'carboxylic acids or'ot other derivatheir respective solutions inzthedorm desired. tives or the cellulose whioh aresoluble in alkali --o.:A process for the production of mixed strucmay be used.'=i-Aiso'mixturesot-these solutions tures foils; films andfilaments from polyamides maybe employed as precipitating baths. 7 It is and'oellulose compounds, which process comprises alsopossibleto make useoi diflerentpolyamides. mixing a solution of a polyamide in mineral acid By changing the dose of the polyamide solution withan ammoniaoalsolution of the cellulose comor oi 'the alkaline cellulose solution there is a pound whileshaping the two solutions to the dechance of varying extensively the composition or sired iorm wherebythe polyamide and the celthe mixed-structures. In this-way there can be l'ulose -compound are precipitated from the reobtained tor-instance filaments which are'oi' dii'- spective solutions in the form desired. ierent composition-indifferent zones. --On. ac- I 

